Timing apparatus



Mamh 16, y1948. w. o. BENNETT, .JR

TIMING APPARATUS Filed June 18, 1941 6 Sheets-Sheet 2 .Wil

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A R EYE.

March 16, 1948. w. o. BENNETT, JR 2,437,929

TIMING APPARATUS Filed June 18, 1941 1 e sheets-sheet s A: EYS

March 16, 1948. w. o. BENNETT, .11R 2,437,929 I TLMING APPARATS I .Filed June 18, 1941 I e sheets-sheet 4 BY M A R EYs.

177 ms 179 7 Jaa 17a '114 March E6, E48. w. o BENNETT, JR 2,437,929

TIMING APPARATUSy Filed June 18, 1941 6 Sheets-Sheet 6 Patented Mar. lo, 1948 TIMING APPARATUS William Ogle Bennett, Jr., Lancaster, Pai, assigno1' to Hamilton Watch- Company. Lancaster,

Application June 18, 1941, Serial No..,39,8,63

4 Claims. (Cl. 'i3-6%V l An object of this invention is to provide improved means for and method of determining a relative rate of operation of a device by determining the differential or lack of differential between given electric current frequencies when one of` said frequencies is governed by the rate of the device.

Another object is to provide improved means for and method of comparing an electric current whose frequency is governed by sounds with an electric current of standard frequency andautomatically achieving an indication of the result of the comparison by operating a mechanical device with each of the currents and comparing the speeds of said devices.

Another object is to provide a timepiece rate testing device including a stabilizer adapted to produce uniform electrical impulses from irregular timepiece sound governed electrical impulses.

Another Objectis to provide a timepiece rate testing device which automatically carries out a test over a predetermined time interval, automatically causes an indicator member to provide a direct indication of the result of the test, and automatically maintains said indicator member in its result indicating position.

Another object is to provide a timepiece testing device which is adapted to carry out a rate test with the timepiece under test in any one of, or any variety of, a universal series of positions, while maintaining unchanged the position ofthe timepiece on its immediate support.

Another object is to provide an improved microphone support which is so formed as to permit universal movement of the microphone.

Another object is to provide means for and method of changing low frequency direct current pulses to alternating current by means of a mechanical vibrator member adapted to be readily driven off its natural vibration frequency,

Another object is to provide means for producing an electric current of a stabilized frequency which is governed by and in step with the intermediate sounds of a timepiece.

Another object is to provide, in an electric current frequency comparison device, a Warningindication operable when and if one of the frequencies departs from given limits.

Another object is to provide improved means and method of automatically carrying out a timepiece rate test over a predetermined time period, and automatically providing a direct indication of the result of the test.

Another object is to provide a timepiece" rate testing device which automatically delays operation a suiicient length of time to permit stabilization Vand synchronization of the `operation of the timepiece and thetesting device.

Other objects and advantages of the invention will become apparent from the following description taken` in connection with the, accompanying drawings,- It lwill beseen that many changes may be made in the Vdetails ofconstruction, arrangement .of parts and method shown and described without departing from. the spirit of the invention as expressed in the accompanying claims. I, therefore, do not Wish to be limited to the exact details of, construction, arrangement oi'parts and steps of the method shownand described, since one form` only has been shovvnH by wayofillustration.

Referringto the drawings:

Fig I "is a schematic block diagram illustrating 'the operation of/the device embodying the invention;

Fig. II is a, schematic partly blocked diagram with the arrangement vof the stabilizingvibrator reed portion of the device shovvrrinFie` I illustrated in detail;

Fig; III isaschematic diagram of vthe control circuits of .the invention;

Fig, IV' is aplan .Viewv of the jointly, operated motors andthe diiferential indicating mechanism of the invention;

Fig.' Vis a. partial side elevation taken in the direction lof Vthe arrowsV-V in Fig. I V;

Fig.i VIis an illustrative View taken on line VI--VI o Fig. IV the assembly being turned and rotated through with respect thereto;

Fig. jVIIzis a view ofthe rotor 183 of Fig.v V;

Fig. VIIIis a section `c-n line VIII-VIII/of FiaVII;

Fig. IX is a view taken along IX-IX of Fig. V without showing the rotor;

Fig, X is a perspective view of thetime delay system including motor, switches, and cams;

. Fig. XI `is a perspective View of the timing Cycle systemincluding motor,A gearing, switches, and cams;

Fig. XII isa plan view of the microphone assembly;

Fig. XIII isA an enlargedv partial viewof Fig. XII taken on line XIII-XIII;

Fig. XIVv is anend elevation `of Fig. XII;

Fig. XV is a section taken'on line XV-XVof Fig. XII;

Fig. a plan viewl'of the-control switch assembly;

Fig. XVII is an end 'elevation of Fig. XVI taken on lineXVII-XVTI; and

Fig. XVIII is a side elevation of the stabilizing vibrator reed which is illustrated schematically nFig. II.

This invention is directed to the provision of improved means and method of measuring or otherwise determining characteristics such as speed, frequency and/or other similar or allied functions or characteristics.

The device described and illustrated herein as representative of this invention provides new and useful improvements in the fields of electric current frequency measurement and of timepiece rate testing devices. It provides means whereby the sounds of a timepiece may be changed to electrical impulses of such a frequency and nature as to permit a quick, accurate, and simple determination of the rate of the timepiece by providing stabilizing means in the form of a mechanical vibrator so designed as to allow it to be readily driven off its natural vibration frequency and thereby make it readily responsive to control by an electric current of a frequency regulated by the sounds of a timepiece and which may or may not depart from the natural frequency of the vibrator.

It provides electrical frequency comparison' means in the form of a differential device jointly operated by a given and a regulated frequency with means to clutch an indicator into operative relation with the differential device for a desired period of time only and automatic means operable when desired, for returning the indicator to effective zero position.

It provides means whereby a timepiece may be tested in any one of a universal series of positions while maintaining unchanged the position of the timepiece on its immediate support so that the timepiece need only be adjusted once with respect to its support and thereafter the support itself may be adjusted to locate the timepiece in the desired different positions of test. This readily permits accuracy and uniformity of comparison of varying positional tests made on different timepieces.

It provides a rate testing device which is automatic to such an extent as to go into action simply by pressing a button and thereafter to automatically carry out the test for a predetermined period of time, including, when needed, automatic time delay means to enable the timepiece and testing .device to become stabilized and synchronized, means to indicate the start and nish of the test, means for stopping the operation of the device and maintaining the reading of the test result, and warning means to indicate when and if the timepiece is agrantly oi rate.

These and other advantages make this invention new and useful and set out a considerable forward step in frequency comparison and timepiece rate testing devices and methods. With the use of the device of this invention timepiece rate testing and particularly testing of cased wrist watchs is so simplified as'to permit the simultaneous carrying out of a plurality of tests on diierent machines and watches by one operator as well as the use of comparatively unskilled operators. The device andmethod of this invention nds an important place in the manufacture of watches, particularly in administering a iinal check on the rate of cased watches.

The rate of a watch is tested, in the device embodying this invention, by causing one motor to be operated in step with the ticks of the watch, and another to be operated at a standard speed, and by comparing the speeds of the motors.

The watch ticks operate the motor by rst being picked up by a microphone and translated into direct current pulses, These pulses operate a mechanical vibrator which stabilizes the pulses. The output of the vibrator is then made to operate a synchronous electric motor so the speed of the motor is dependent upon the frequency of the watch ticks.

At the same time another synchronous motor is operated at an eiectively constant speed. The motors are linked so as to produce a diierential speed in a device which operates an indicator. This indicator accordingly, by the extent of its movement in a given time, indicates the diiference in speed of the motors and, therefore, the relative rate of the watch, and by the direction of its movement, which motor is faster and therefore whether the watch under test is fast of slow with respect to an effective constant.

The operation of the devi-ce is automaticall;l controlled and carried out. When a. watch is first positioned on the microphone, a momentary starter switch is pressed. This puts into operation a delay system which permits the watch and testing device a predetermined period of time in which to become stabilized and synchronized. The delay system thereafter energizes a timing cycle system which automatically carries out the test over a given period of time, and automatically stops the test when the period is over.

After the watch has been on the microphone a suilicient length of time to become stabilized and synchronized with the testing system, a short cut starting switch may be used, thus operating the timing cycle system directly, without using the delay system.

Referring to Fig. I the device embodying the invention includes a source I of electric current having a standard or eectively constant frequency and a microphone unit 2 which is adapted to pick up the sound vibrations of a watch and translate them into electrical impulses. The current from the standard source I preferably 60 cycles, is made to operate a standard frequency motor 3, See Fig. IV, preferably at 1800 R. P. M. The electrical impulses from the microphone 2 are passed through an amplifier 3a and a grid controlled gaseous discharge thyratron type tube The output of the thyratron type tube is then made to operate a mechanically vibrating stabilizer reed system 5. See Figs. I, II, and XVIII. This output of this reed arrangement is passed through an amplier and direct pulse producer 6 whose output, preferably 30 pulses per second, in turn is made to operate a watch motor l. See Figs. III and IV. Thus the watch motor is operated` at a rate dependent upon the frequency of the sounds or ticks of the watch. The standard motor 3 and the watch motor I are so linked as to operate the differential indicator system 8, which, as seen in Fig. IV, includes a rotor ISE, linked with motors 3 and I only by magnetic force, and drive wheel IIl'I driven by rotor IUS and adapted to drive indicator dial |08 when clutch I5 operates under the action of its solenoid 45.

The differential indicator system 8 is controlled through a control system which includes two starting switches. These are the delay switch 9 and the short cut switch Ill, and the mechanical set-up for these is shown in Fig. XVI. Use of either of these switches will energize the timing cycle system Il. When the delay switch 9 is operated it energizes the time delay system I2 which automatically operates for a given period of time and thereafter energizes the timing cycle system ll. As is indicated in Fig. I, when the short cut switch lb is operated the timing cycle system l i is directly energized and the time delay System l2 is not operated.

The delay switch 9 is used when the Watch is rst put on the microphone and the time delay system l2 is thereby operated in order to give the watch and the testing circuit an opportunity to become stabilized and synchronized. The short cut switch lil is used when the watch is already on the microphone and is merely being moved to a different position or when it is known to be already stabilized.

The timing cycle system El operates a brake I3 to hold or release the indicator |05, a zero return device it comprising solenoid t6, cam Ille, and lever llt, as shown in Fig. V, which when energized, automatically returns the indicator 68 to its effective zero position, a clutch l5 which moves the indicator into or out of operative relation with the rotor let, and a timing cycle indicator it which designates the start and nish of the test period, and which includes a pilot light lit, Figs. III and IV. This timing cycle indicator iii is also operated by the time delay system i2 and when the time delay system is deenergized after the energizing of the timing cycle System l l, the control of the timing cycle indicator it is dropped from the time delay system i2 and is taken over by the timing cycle system l l.

The stop and overbank drop out system Il' is initially energized by the timing cycle system li and is thereafter controlled by the nature of the output of the amplifier in the block 6i of Figs. I and II and it includes a dial light 95a which goes out if the test is not going right.

The control system is notable in that the control moves from point to point, that is, the delay switch Si is a momentary switch and it merely energizes the time delay system l2 and then drops out of operation. rIhe time delay system in turn energizes the timing cycle system ll and then drops out of operation. This is also true of the short out switch lil. The time delay system and the timing cycle system both operate themselves for a given period of time and then drop out automatically. This is also the case in the operation of the drop out system l'l which is initially energized by the timing cycle system Il and thereafter operates itself as long as the output of the amplier block t is maintained within given limits.

An important feature of this invention is the stabilization of the electrical impulses which are formed when the device picks up the ticks of the watch. The sound vibrations which originate in the so called tick and took of a Watch or timepiece are not in all cases produced at regularly spaced intervals and therefore the electrical impulses which are formed when these sounds are picked up by a microphone are not produced at regular, equally spaced intervals. In order to get an accurate test of the rate of a watch it is essential that the electrical impulses brought about from the watch sounds be regular and produced at equally spaced, stabilized intervals.

rihis stabilization is accomplished'in this invention by utilizing a mechanical vibrator I9, see Figs. II and XVIII, with this vibrator so formed and/or adjusted as to have a calculated natural vibrating frequency of its own. This frequency is carefully calculated to a small multiple of the frequency of electrical impulses governed by the sounds ofl an accurately operating timepiece.

The vibrator is so formed as to be readily` driven oft" its natural vibrating frequency so that variation in the frequency of the electrical impulses in the output of the microphone will so control the vibration of the reed as to keep it in step with the frequency of the watch sounds. In this manner the sounds of the watch control the vibration of the reed and the vibration of the reed stabilizes and makes uniform the electrical impulses caused by the sounds of the watch.

The watch motor energizing system is illustrated in Fig. II with the microphone 2 and amplier 3a, and thyratron type tube 4 leading up to the reed system 5 and with the output of the reed going through the amplifier and direct current producer 6 to operate the watch motor l. The output of block 4 periodically energizes an electromagnet I8 and since the reed I9 is xedly supported at its end 2B and is free to vibrate throughout the remainder of its extent and since the free end 2l of the reed I9 is of magnetic material and is, in its position of rest, at a point to one side of the core 22 of the electromagnet i8, when the electromagnet is energized the reed il will be pulled sideways and its vibration started or maintained. The reed I9 has iixed transversely thereon a permanent magnet 23 which moves with the reed when it vibrates and each end thereof moves through one of a pair of pick up coils 24 and the movement of the permanent magnet 23 through the coils 24 produces electrical impulses in step with the vibration of the reed and therefore the sounds of the watch and these impulses are produced at effectively equally spaced intervals certain of which arevaried by corrective impulses impressed on the electromagnet in accordance with the timepiece operation.

The pulses which energize the electromagnet i8 are impressed thereon at regular but differently spaced intervals in accordance with the sounds of the Watch. It is this irregularity which is stabilized and made uniform by the operation of the vibrator reed I3. This reed has essentially the operation of the balance wheel of a watch and the electromagnet I8 has essentially the operation of an escapement of a watch, that is, the reed I9 vibrates through its own inertia and gets intermittent energizations from the electromagnet which are such as to keep the reed vibrating and in step with the watch sounds. The movement of the reed, however, is uniform so that its output is in the form of equally spaced electrical pulses, with periodic phase changes.

In order t0 -give the reed the greatest possible energization with the power available the free end 2i Vthereof is placed close'to the electromagnet I3, and in order to give the permanent magnet 23 the greatest possible movement through the pickup coils 2li, it is positioned on the reed i9 close to the free end 2l. This arrangement brings the coil of the electromagnet l-linto relatively close positional relation with the pickup' coils 2li so that there is an electrical linkage between the electromagnet I8 and the pickup coils 21% which is undesirable since if unchecked it would introduce irregularities into the output of the reed system, Accordingly, a balance circuit is set up with a take -oiT from the coil of the electromagnet I3 which directly feeds suicient current into the pickup coils 24 to offset the current in the coils resulting from the above mentioned undesirable linkage. This balancing effect is made adjustable through variable rheostats 25.

Referring to Fig. III the timing device is brought into lgeneral' energization by a main switch which energizes the standard frequency motor 3 through its input 26, the 110 volt A. C. source 21, and the 6 volt D. C. source 28.

The main control divisions of the control sys- Y tem are illustrated in Fig. III and are in areas enclosed by dotted lines. The time delay system |2 (Fig. I) comprises the time delay relay system 29 and the time delay m-otor system 30. The relay system comprises the relay 3| and associated switches 32, 33, `and 34. Th'ese switches are shown in the positions they hold when the relay 3| is deenergized, that is, 32 and 33 are open and 34 is closed. Similarly throughout Fig III, the switches are shown in the positions they hold when their associated relays are not energized. The above mentioned switches as well as those adjacent and operated by cams, `are in the positions, and the cams are in the positions, which they hold when the systems are ready to start a test.

In the motor system 33,` cams Sla and 32 are operated by the delay motor 33a.

The timing cycle system (Fig. I) comprises the timing cycle relay system 34a and the timing cycle motor system 35 and in the timing cycle motor system 35 the cams 36 and 31 are operated by the timing motor 38.

The stop and overbank drop out system i1 (Fig. I) includes control system 39 with transformer 4D, rectifier tube 4| and relay 42 with its associated switches.

When the rate testing device is set and ready fcraction the main pilot light 42a is-on, indicating the general energization of the device, the time cycle pilot light 43 is on, indicating that neither delay nor timing systems are operating, the dial light 36a is out, indicating that the overbank and timing relays are not energized and no test is being carried out, the standard frequency motor 3 is going, the watch frequency motor 1 is not yet energized, the time delay motor 33a and the time cycle motor 38 are both stopped, the brake I3 is on and holding the indicator dial |08, and the brake solenoid 44 is not energized. The clutch |5 is disengaged so that the indicator dial is not being driven and the clutch solenoid 45 is not energized. The set back device |4 isout of operation and its solenoid 46 is not energized so that the indicator dial may or may not be at its eective zero position. The overbank device |1 is out of operation and its solenoid 42 is not energized.

The situation is then that the standard frequency motor 3 is running and itis driving a shaft |28, through magnet connections, which operates a gear wheel |61 preparatory to clutching in with the indicator dial |68. The indicator dial at this point is not driven The timedelay button is pressed so as to close switch 9 and the time delay motor, its cams and associated switches go into action. The time cycle pilot light 43 is put out by this action. When the time delay cycle is over the main cycle has automatically been started, and the time cycle pilot light remains out. The set back and the overbank relays 46 and 42 are briefly energized when the main cycle is started by energizing the main relay 41, that is, for a short preparatory period just prior to the actual timing period. The overbank relay 42 is then kept'energized by a holding switch 48 but the set back is released after the short preparatory period by deenergizing solenoid 46. At the start of the actual timing period the brake is released by energizing its solenoid 44 and 51 as before.

and this frees the indicator dial for rotation. At the same time the clutch is operated by energizing its solenoid 45 so that the indicator dial is connected with the rotating drive shaft, When the overbank relay 42 is energized at the start of the brief preparatory period the watch motor 1 is put into operation and is kept in operation, barring reed amplitude Variation beyond given limits, throughout the preparatory and actual timing periods.

At the end of the actual timing period the time cycle pilot light 43 goes on, the clutch and brake solenoids 45 and 44 are deenergized so that the indicator dial is no longer driven through the clutch and the dial is held in its test result indicating position bythe brake. The overbank relay 42 and therefore the watch motor remains in operation just as long as the reed amplitude remains within the proper limits. The overbank relay 42 may be made to release by removing the watch from the microphone or by changing the position of the watch in such a way as to cause it to overbank or operate suiciently erratically to vary the reed amplitude and thereby deenergize the relay 42 and stop the watch motor 1.

The time delay system is started by closing the switch between contacts 49 and 50. It will be seen that the side 5| of the time delay relay 3| connects directly to contact 52 of the 6 volt source 23. The side 53 of the time delay relay 3| connects with contact 54 of the 6 volt source 28 through switch 55 in the delay motor system 36, across poles 50 and 49, through switch 56 in the timing relay switch system 34, through switch 51 of cam 36 of the timing motor system 35, and directly to contact 54.

Energizing the delay relay 3| opens switch 34 and closes switches 33 and 32. Switch 32 keeps relay 3| energized when the momentary switch 9 of contacts 49 and 50 is released. It will be seen that the side 53 of the delay relay 3| in this instance is connected to the contact '54 of the 6 volt source 28 through switch 55, then directly to the switch 32 and thereafter through switches 56 The closing of switch 33 puts the time delay motor 33a into operation. The contact 58 of this -motor is connected directly to contact 59 of the 110 volt source 21. The contact 66 of this motor is connected to contact 6| of the volt source 21 through switch 33 and then direct. In opening switch 34 the time cycle pilot light 43 is put out since side 62 of this light is connected to con-tact 52 of the 6 volt source 28 directly except for passing through switch 34 and that side 63 of the pilot light 43 is connected to Contact 54 of the 6 volt source 28 through switch 64 of cam 31 of the timing motor 38, and through switch 65 of the timing relay system 34.

The delay motor 33a rotates its cams 32 and 3|a in a counter-clockwise direction when set up in the arrangement as shown in the diagram. The rotation of cam 32 causes the closing of switch 66 and with Ithis connection made, the delay motor 33a will keep going regardless of switch 33 as long as cam 32 keeps switch 66 closed, so that even though the delay relay 3| is deenergized, and switch 33 opened, the delay `motor 33a keeps going since the side 66 instead of being connected through switch 33 now is connected to switch 66 and thereafter direct to contact 6| of the 110 volt supply 21.

Cam 3|a, of delay motorV system 30, in being rotated holds switch 55 closed for the time delay period desired, which is, preferably, 12 seconds, although any other desired period may be used.

At the end of this time the finger 67 drops over shoulder 68 of cam 3io and switch 55 is opened and switch 38 is simultaneously closed. The action of the opening or switch 55 is to deenergize the delay relay 3| since the switch 55 is in the line between the side 33 or the delay relay 3| and the contact 5d oi the 6 volt source 23. It will he seen that the action of the deenergizing of the delay relay 3| is as follows: The holding switch 32 is opened so that the relay 3| is no longer held in energized relation and will not again become energized until the switch connecting the starting contacts 58 and i9 is again closed, providing the timing relay system 35i is not operating at the time ci closure of said switch, in which case closing switch 8 will have no effect. The switch 33 is opened and this has no immediate eiect. However, it does mean that when cam 32 is so rotated as to open switch 65 the delay motor 33a will stop, since its original starting switch 33 is now open. Switch 31% is now closed and this closing would ordinarily light the time cycle pilot light d3 but since the switch 68 (cam 3m) has been closed and the timing relay :i7 accordingly energized, switch 35 of the main timing relay system 3f! is open :and Isince this is in the line from the side 63 of the pilot i3 the pilot remains out.

'I'he main timing starting relay 47 is now energized, the time delay relay 3| deenergized, and the time delay motor 33a still running, because the switch 88 is closed through the action of cam The reason for keeping the motor and cam 32 operating is to reset cams 32 and Sla to starting position and as soon as this position is reached on the cams, that is, the position as shown in Fig. III, the switch 88 is opened by the dropping of iinger 78 over shoulder 7| of cam 32 and the time delay motor 33a is stopped. At the saine time switch 55 is closed so that the time delay relay 3| may again be energized when starting contacts i9 and 58 are connected, and switch 68 is opened. This, 68, is the energizing switch for the vmain starting relay 47.

The side -72 of the timing relay 47 is connected to contact 52 of the 6 Volt source 23 through contact 3d of the delay relay system 3|. Incidentally, the main starting relay i7 cannot be energized while the time delay relay 3| is energized since in that case switch 34 is open. The side 73 of the timing relay il is connected to contact 54 of the 6 Volt source 28 through switch 68 of cam tid when closed, and through switch 57 of cam 36 of the timing motor 33. When the main starting relay i7 is energized it is held in that state hy switch 7d when closed irrespective of switch 63 so that switch E8 may be closed only briefly and may subsequently open, as it does, without deenergizing the main starting relay 47.

With switch lli closed, side 72 of the timing relay c7 is still connected to contact 52 of the 6 volt source 28 in the same way, but side 73 is connected to contact 54 of the 6 volt source 2B through switch 7d and thereafter through switch 57 as before.

v The main starting relay i7 is now energized and since switch 53 is accordingly opened, the time delay relay 3l is thus prevented from operating since switch 88 is in the line between side oi the time delay relay 3l and contact 54 of the 6 voit source 28 as described above. It has been shown that switch 74 is the holding switch for the main starting relay i7 and this is how closed. Switch i5, which is now closed, energizes and starts the main time cycle motor 10 38. The side 18 of the time -cycle motor 38 is connected directly to contact 59 of the 110 volt source 27. Side 77 is connected to contact 8| of the 110 volt source 27 through switch 75, when closed.

While the main starting relay i7 has been shown as being energized through the switch 68 it is pointed out that this is the manner of its energization only when the time delay relay 3| is utilized and rst energized. The main starting relay @7 may be energized directly by closing the switch between the short cut starting contacts 78 and 79. In this case, the time delay relay 3| being deenergized, switch 34 is closed, and side i2 of the main starting relay is connected to contact 52 of the the 6 volt source 28 through the closed switch Sli. Side 73 of the main starting relay 47 is connected to the contact 54 of the 6 Volt source 28 across the contacts 78 and 73 of the short cut switch I0, and through switch c7 of cam 36 of the timing motor 38, so that the main starting relay i7 may be energized either by connecting short cut contacts 78 and 79, or by closing switch E8 as long as switch 34 is closed in either instance, that is, as long as the delay system 28 is not operating.

Switch 79 (timing relay system 3i) is now open but its opening has no immediate elect on the system. This switch is used later in combination with switch 38 of cam 37 to operate the brake solenoid lili. Switch 8| is now closed and therefore the brake solenoid ifi is energized and the brake is oi, that is, the indicator dial |88 is released so that it may rotate. The brake solenoid it@ is energized since its side 62 is directly connected with contact 52 of the 6 volt source 28 and side 83 is connected with contact 54 of the 6 volt source 28 through switch 8i. Switch 85 is now open and this has no immediate effect although it is, later, when closed, used as a part of the line used to energize the clutch solenoid 65. Switch 84 is closed and the set back solenoid 46 is accordingly energized. Side 85 of the set back solenoid i6 is connected directly to contact 52 of the 6 Volt source 28 and side 86 thereof is connected to contact 5d of the 6 volt source 28 through switch 84, since it is now closed.

Switch 87 is now closed and this causes the overbank relay i2 to be energized. The side 88 of the overbank relay G2 is connected directly to contact 39 of the watch motor input 98 and the side Si of the relay i2 is connected to the contact 92 of the watch input 98 through switch 81, of the timing relay system 3d, when closed, through rectier tube 4| loy way of resistor .93 and plate outlet 8d. The overbank relay 42 being energized, switches 5S, 35, and 98 are closed. Switch 48, being closed, acts as a holding switch to keep the relay :i2 energized. Side 88 is now still connected directly to contact 89 of the input 8i) and side 9| is still connected to contact 32 of the input 98 but it now connects through switch i8 and tube il instead of switch 87. Switch 35 is now closed and this lights the dial light 98a. It will be seen that this light is connected directly across the line of the main pilot light 52a which receives its power, as does the iilament of the tube 4|, from the drop out transformer L38, which is energized directly from the 1li) volt source 27. rIhus if the overbank relay z2 is deenergized for any reason the dial light 98a goes out. Switch 36 is now closed and accordingly the watch controlled motor 7 is energized. Side 97 of this motor is connected directly to contact 98 of the watch motor power 1I input 90, and side 99 is connected 'to contact 92a of the input 90 through closed switch 96.

The purpose of the rectifier tube 4| is to produce direct current to operate the overbank relay 42 under the control of the reed amplitude. The alternating current output of the amplifier of the block 6 in Fig. I is tapped to supply the input to the overbank relay 42 through the rectier 4| across input contacts 89, 92 and 98. Accordingly, if the amplitude of vibration of the reed 5 falls below a given limit the overbank relay 42 is deenergized and the dial light 96a goes out as a warning that the test is not being properly carried out.

The amplitude of the reed falls below the limit necessary to keep the overbank relay energized when the flow of timepiece sounds is non-uniform or non-existent as is the case respectively when the timepiece overbanks or stops.

If desired, the rectifier tube 4| and transformer 40 may be dispensed with by taking the power for the overbank relay 42 from the output of the 30 D. C. puise portion of the block 6 of Fig. I.

Returning to the main starting relay 41, this is now energized and its various switches are positioned and have their functions as described above, one of which is the starting of the time cycle motor 38. This motor drives cams 31 and 36. Cam 36 is so formed that after a brief period, preferably 6 seconds, although any other desired period may be arranged, switch 51 is opened when finger |02 drops over shoulder |03. This has the immediate effect of deenergizing the main starting relay 41. When this happens the main timing cycle (preferably 30 seconds) begins. Switch 81 is opened and this makes the overbank relay 42 dependent entirely upon the closed switch 48 to keep it energized. Switch 84 is now open and this deenergizes the set back solenoid 46 and takes the set back out of operation thus leaving the indicator dial |08 free to rotate from effective zero.

Before switch 51 is opened, cam 31 causes switch |00 to close, switch 64 to open and switch 80 to close. Switch |00 keeps the time cycle motor 38 running in spite of the fact that switch has now opened due to the deenergizing of the main relay 41. In this connection it will be seen that side 11 of the motor 38 is now connected to contact 6| of the 110 volt source 21 through switch |00 (cam 31) so that the motor 38 continues to operate in spite of the fact that the main relay 41 has been deenergized. Switch 64, now open, causes the time cycle pilot light 43 to remain out, in spite of the fact that switch 65 (relay 41) which ordinarily would light this pilot light, is now closed, that is, side 63 of the time cycle pilot light 43 is now prevented from being connected with contact 54 of the 6 Volt source 28 by the fact that switch 64 is open. If switch 64 were closed and the main relay 41 deenergized the pilot light 43 would light since side 63 would then connect with contact 54 of the 6 volt source 28 through switch 64, and switch 65. Switch 80 is now closed. VThis has the effect of keeping the brake solenoid 44 energized and the brake off.

The side 83 of the brake is now connected to contact 54 of the 6 volt source 28 through closed switch 19, closed switch 80, and closed switch 85. Therefore, the brake remains off with its solenoid 44 energized in spite of the fact that switch 8| on which it previously depended is now open. Switch 80 being closed causes the clutch solenoid 45 to be energized and the indicator dial |08 to be connected with the differential rotating drive shaft I 28 which now, since both the standard frequency motor 3, and watch motor 1 are operating, expresses the differential between the speeds of these motors. Therefore, the clutch 5 brings the indicator dial |08 into operation just for the timing (30 second) period. With switch 80 closed the side |0| of the clutch solenoid is connected directly to contact 52 of the 6 volt source 28 and side |02 is connected to contact 54 of the 6 volt source 28 through closed switch 8|), and closed switch 65.

The time cycle motor 38 continues its operation regardless of the fact that the main starting relay 41 has been deenergized andthe switch 'I5 opened, through the holding switch |00 under the controlling action of its cam 31. After a desired time period has passed, for instance, the 30 seconds which is preferable for an' actual testing period, cam 31 causes switch |88 to be opened again when finger |04 drops over shoulder |05, switch 64 to be closed and switch 80 to be opened. The opening of switch |00 stops the time cycle motor 38 since |00 is the holding switch for that motor when the main relay 41 is deenergized. Switch 64, now closed, lights the time cycle pilot light 43 indicating the end of the timing period. Switch 80, now open, causes the clutch solenoid 45 to be deenergized and the clutch thereby released so as to stop the driving of the indicator dial, and also causes the brake solenoid 44 to be deenergized and thus permits the brake to operate under the action of its solenoid spring |21, Fig. IV, and hold the indicator dial |08 in the position it has reached under the differential action of the standard frequency and watch motors 3 and 1.

At the same time cams 36 and 31 have been brought around to starting position as shown in Fig. HI, so that when the main starting relay 41 is again energized the entire system is ready to repeat the test.

Mechanical portions of the control arrangements include the momentary switch arrangement of Fig. XVI which shows the set up of the delay starting switch 9 and the shortcut switch I0. This arrangement comprises a pair of micro switches which are fixed to a. plate ||2 by means of screws ||3. The micro switches are so positioned on the plate I I2 that their contacts ||4 are disposed in opposite and aligned relation with each other between the micro switches. A rotatable shaft ||5 extends between the micro switches and above their contacts and is rotatably supported in a pair of upright posts H6. A blade member ||1 is supported by the shaft H5 and extends downwardly therefrom between the micro switches The blade ||1 has a pair of contact members ||8 thereon in alignment with the contacts ||4 of the micro switches so that when the shaft ||5 is rotated in its supports ||6 one of the contacts ||8 is pressed against its adjacent micro switch ccntact so as to make the desired connection.

The blade ||1 is secured to the shaft ||5 at a point removed from the micro switch contacts I |4 and extends in substantially free resilient relation from its connection to the shaft ||5 to the contacts H4 so that there is a resilient action in the finger ||1 when the shaft ||5 is so turned as to press one of the contacts |18 against its adjacent micro switch contact ||4. The shaft ||5 supports a yoke ||9 which turns with the shaft and is so positioned as to hit against the plate ||2V when the shaft has been rotated a small amount. This yoke provides a safety factor which 1:3 prevents `excess pressure being exerted ontne micro switch contacts lill. The shaft H5 also supports@J yoke having a nger piece |2| on each end thereof to provide a direct and simple method of turning the shaft in order to operate one 01'. the other of the switches.

When switch S'is operated the time'delay Inotor system 35 is energized. This system is illustrated in Fig. and comprises a motor 33a, and cams 3 lav and 3'with their associated switches 66, |53 and 55. rIhe cams Ela and 32 are rotated. oy the motor 33a in the direction oi the arrow |22 so that theV iingers 1|) and 51 movein and out ofthe cam recesses provided by the shoulders 1| and 69.

In the course orbits operation the time delay motor system 3E) causes 'the time cycle motor systeml 35 to be energized and the mechanical portions of Athis system are illustrated in Fig. XI wherein is shown the motor 38, cai/ns 35 and 31 and their associated switches 51, Hill, 64 and 80. The cams and 3l' are rotated by the motor'38 in the direction of the arrow |23 through the action-of gears ltd and |25. These gears are so calculated and formed as to rotate the cams'at just the desired speed to carry out the timing cycle of the test in the time required to rotate the cams the-amount necessary to operate the switches.

The brake device is illustrated in Fig. IV and comprises solenoid with brake i3 having a pointed end |26 which is adapted to contact the dial indicator |93 under the action of spring |21 when the solenoid ed is not energized.

The clutch arrangement is also illustrated in Fig; IV and this functions to operatively connect the dial indicator Hi8 with the rotor |05 associated with the watch motor 1 during the timing period of the device. The rotor |95 drives shaft i228 whichin turn drives gear members |29, and itl and shaft |38 to which is rigidly connected a clutch member lili which accordingly rotates with the rotor me of the watch controlled motor l. The indicator dial ica is mounted for free rota-tion on the shaft I El) and is adapted to be operatively connected with and rotate with rotor |555 when the clutch arm |312 is moved about its pivot '|33 under the action of the clutch solenoid t5.

This movement of the clutch arm |32 causes the indicator dial |33 to move longitudinally of the shaft i3d and to bring the clutch face |33a into contact with the rotating clutch member ili se as to cause the indicator dial |83 to rotate in accordance with the movement of the rotor ist. The ciutch arm |32 has pin members ld exten ding therethrough which when the solenoid (i5 is actuated are caused to press against a sleeve |35 which in turn bears on a ball race |35. The sieeve E35 is accordingly stationaryand the remainder oi the ball race |35 and thek clutch face are rotated when the clutch is actuated. The indicator dial lili! is connected to the clutch face through a bushing |31 by means of pins having a member |39 between their heads andthe bushing |31 so that it will be seen that the indicator dial |138 is resiliently connected to the sleeve |31 and the clutch |5.

The zero return system is'illustrated in Fig. V and comprises a heart shaped cam m9 which is mounted so as to rotate freely on the shaft |35 and rigidly with the indicator dial |53 so that movement of the heart shaped cam about the shaft |35 will correspondingly move the indicator dial Hi8. The heart shaped cam |39 is operable the yoke ldd.

by-means oa -lever HIJ pivotly supported on an upright |40 and having'a roller |4| adapted to contact the periphery of the cam |09. The lever ll'has a plunger member |42 pivotly connected thereto with the lower end of the plunger adapted to be acted on by the set back solenoid 4B. When the indicatordial |08 is free to rotate about the shaft |33 actuation of the set back solenoid i5 will cause the lever H0 to'be pulled down and the roller |4| to press on the periphery of the heart shaped cam |89 so as to rotate that cam until the roller IM Yrests in the zero position |43 of the cam. A keeper member |44 in the form of a resilientspring is so positioned as to resist the movement of the roller |=3| past the high spot of the cam so that a resilient deterrent to the complete rotation of the cam and indicator dial is thus provided.

In each of the solenoids as described there is a spring member to push the actuating arm out of the solenoid when the solenoid is not actuated. The spring member of the set back solenoid 45 is illustrated at |55. That of the brakesolenoid is illustrated at |21 in Fig. IV and that of the clutch solenoid is illustrated at seem Fig. 1v.

The microphone assembly, see Figs. XII-XV, comprises a shaft |51 rotatably supported on a plate idf-3. At the forward. end of this shaft is mounted, in hired relation so as to be rotatable with the shaft, a yoke -member Hla substantially semi-circular. in shape and extent with said mounting to the shaft being located substantially centrally of this Vsemi-circle and secured by a nut M9 or similar suitable holding means. At each endV of the yoke ila'is mounted an inwardly extending bearing member i553, each of which is inralignment with the other. Supported on these bearing members is a cup like member |5| which is mounted 'on said bearings for rotation within the yoke and about an axis at Vsubstantially right angles to that about which the yoke itself is movable. It willbe seen, therefore, that the cup like member |5| is so arranged as to have a uni` versal movement.

Within the cup member is a piezo-electric crystal I 52 which is supported in the cup |5| on sponge rubber or other suitable resilient mountings |53, see Fig. XV.

There are two wires attached to this crystal, one of which (|54) is connected directly to the bottom of the cup as a ground. This ground follows thevarious bearings and supports to the casing of the assembly. The other wire |55 is the one which picks up the electrical impulses oi the crystal |52 and this wire extends through one of the cup bearings |50 to one end |55 of This wire |55 is connected in its cup bearing |53 to a hairspring |51 (Fig. XIII) providing a pigtail type of connection one end of which'is attached to the above mentioned wire and the other lto a wire leading back in a recess |55 of the yoke to the yoke support and rearwardly through the supporting shaft |41 to a contact ring |59 mounted on the rear of the shaft |41.

The spring |51 is mounted so as to be effectively concentric with the cup bearing |59 through which the pickup wire |55 extends.

The cup l5! has a metal cover i5@ `with flanges l5! to t .within the cup and with these flanges recessed at diametrically opposed'points to receive the bearings |53.

The cover |56. has a felt pad |62 on the top thereof and both pad and cover are centrally perforated. This perforation contains a headed shaft and a spring pressed ball 15 pin |63 with the head at the lower end of the pin and lying within the cup in Contact with the crystal |52. The assembly of this cup is such that this pin extends slightly above the felt surface. At one side of the cup on the outside there is mounted a blade spring |64 which extends upwardly and then forwardly and downwardly to overlie the top of the Ycup and the upwardly extending end of the pin member |63.

In operation, the spring |64 is lifted and a watch is inserted beneath it in such a manner that the spring bears on the watch which in turn contacts the upper end of the pin and forces the headed end of the pin against the crystal.

The function of the spring |51 is to permit the rotation of the cup on its bearings while the electrical contact from the crystal is maintained without twisting of a wire. On the 'bearing |50 opposite that containing the spring there is mounted a stop pin |05 which may be made to contact a second stop pin |60 which is mounted on the yoke |48 in order to prevent the continuous turning of the cup on lts bearings in one direction sufficiently to wind or unwind the spring too great an extent.

The same bearing which supports the stop pin has indexing means associated therewith so that the cup in its rotation may be quickly and readily moved to different positions. This indexing means consists of V slots in the bearing |50 and a single ball |61 housed in a recess in the end of the yoke |48. The resilience of the yoke is utilized to force the ball member into each of the slots as the cup is rotated on its bearings |50 and the ends of the yoke are forced apart a slight amount when the cup is turned and the ball Ibears on such points of the cup bearing as are not slotted.

The spring member |64 for holding the watch on the face of the microphone is so contoured as to prevent the turning of the cup more than an amount suicient to obtain the desired positions, yby contacting the central part of the yoke |48, and acts as a stop in the same way as the previously mentioned stop pins do and for the same reason, namely, to prevent damage to the hairspring.

The supporting shaft |41 for the yoke member is hollowy and the Wire extending from the microphone crystal extends through the center of this shaft and is attached to the contact slip ring |59 mounted on the rear of the rotatable shaft |41 and insulated therefrom :by means of a plastic disc |68. The disc |68 and slip ring |59 are mounted on a supporting metallic ring |69 which is rigidly mounted on the hollow shaft |41. The hollow shaft is indexed in its rotation in a manner similar to the indexing of the rotation of the cup member, that is, there are slots in the mounted within the plate to operate the indexing.

The electrical impulse from the crystal |52 is picked up from the slip ring |59 by means of a spring pressed plunger |10a which rides continually on the periphery of the slip ring. This plunger is mounted in a casing which is in turn supported on the plate |48. The impulses picked up 'by this spring pressed plunger are thereafter directly routed by cable to the amplifier unit 3, see Fig. I.

'Ihe reed I9 of the vibrator unit 5 is further illustrated in Fig. XVIII in which is shown the electro magnet I8, the reed member I9 with lts fixed end 20 and the pick up coils 24. The reed is so formed as to vibrate at a particular natural frequency and in order to enable it to do this it has a relatively thin portion |1| adjacent its xed end 20. Also in order to provide an adjustment of the period of vibration of the reed a slidable weight member |12 is mounted on the reed |9 for movement longitudinally thereof and is provided with a set screw |13 in order to hold it in adjusted position.

The standard frequency motor 3 and the watch motor 1 are linked as is illustrated in Figs. IV and V through a shaft |14 which is broken in Fig. V so that only the watch motor 1 is shown. The shaft |14 is driven by the standard motor 3 at the standard frequency. This shaft extends through the motor 1 and has attached at its outer end an assembly comprising a pair of magnetizable poles |15 which are attached directly to the outer end of the shaft, an insulating member |19 which rotates with the shaft and the magnetizable member |15 and a second set of inagnetizable poles |11 which are in the form of a ring but which have no direct magnetizable connection with the-shaft |14 although they rotate with `it and in fixed relation with magnetizable poles |15 due to the insulating connection member |10. At a point on the shaft |14 spaced from its free end and adjacent the standard motor 3 is attached a cup like member |18 which rotates with the shaft. The annular edge of this cup like member lies in substantial alignment with the annular ring |11 and is separated therefrom by a supporting plate |19. This plate is stationary so that the annular member |11 and the cup |18 rotate on on either side of it. Both the cup member |18 and the support of the coil as well as the ring of the magnetizable poles |11 are slotted to prevent eddy current action.

The plate |19 rigidly supports the driving coil |80 of the watch motor 1 in fixed position within the cup member |18, and plate |19 is magnetizable.

The action of the watch motor 1 is as follows:

The input derived from the ticks of the watch is impressed upon the coil |80 and this in turn sets up a polarity in the shaft |14 which is being driven by the standard motor 3. One pole is at the forward end of the shaft and gives one polarity to the poles |15 and the other pole is at the rear end of the shaft but is carried around through the cup member and made to jump the gaps between the cup member |18, the pole member |11 and the fixed plate |19 so that pole pieces |15 and |11 are given opposite and intermittent polarity, with the frequency of their energization being controlled by the ticks of the watch. The rotor |05 is mounted within the opening formed by the pole members |15 and |11 free of any connection with the watch motor 1 other than the magnetic connection between its permanently magnetic poles lill and the poles |15 and |11 of the watch motor. See Figs. VII-IX.

The motion of the rotating poles |15 and |11 combined with the frequency of the watch tick governed impulses on those poles creates such an attraction for the rotor |06 as to hold that rotor stationary providing that the frequency of the watch tick governed impulses has the effect of driving the watch governed motor at the same speed as the standard motor. In the event that the speeds are different the rotor |06 will rotate at a rate depending upon the difference and in a direction depending upon whether the watch governed impulse frequency is such as to effectively drive the watch governed motor faster or slower than the standard motor.

Thus the rotor |06 driving the shaft |28 exof the standard motor. The v'rotor is `formed, as -is illustrated-in Fig. VIII, of acentral composite permanent magnet |82 and separate poles '-ISI which are pressed thereonitl'irough the action of a cup like holding member |83. As indicated in Fig. VII likepolesin-this permanent vmagneta diametrically opposite each other.

The frequency'of watch ticks is normally five per second. In order to drive a motor lb-y these watch ticks it is flrstneces'sary to change the sounds of the ticks to electrical impulses and then to amplify the impulses to a sufficient strength to operate the motor and Vsii'n'ulta'neously to increase the frequency suiicien-tly to operate the motor.

The sound of the Watch ticks is picked up by the microphone so that the microphone output is direct current pulses at the rate of ve per second. These-pulses are ampliiied andmade to operate the thyratron type tube which accomplishes further amplication. The vibrator reed is given a natural period of l cycles per second. This is made to vibrate by the energization of the electromagnet with the periodic output of the thyratron tube so that the reed vibrates several times in between each impulse from the electromagnet. The reed is so formed that the impulses in the electromagnet may momentarily retard or accelerate the vibration of the reed so that the alternating current output of the reed is changed in phase upon the changing of the vibration of the reed. The electromagnet accordingly not only drives the reed but also periodically changes its vibration to bring it in step with the watch ticks.

The nature of the electrical pulses in the system prior to the reed may be described as a unliorm series of repeatedly occurring pulses with each pulse spaced a different amount from its preceding adjacent pulse and the pulses of the output of the electromagnet may be described as a uniform series of groups of pulses with each group comprising equally spaced pulses and when the Watch is off time, with each group spaced from its preceding group a different amount than from its following group.

The function of the reed is to multiply the frequency of the electrical impulses derived from the watch ticks and to effectively iron out irregularities in spacing between the watch ticks. The natural vibration period of the reed is such as to average out variations in spacing and yet the reed is so formed as to permit such temporary change in its vibration under the action of the Watch tick pulses on the electromagnet as to change the phase of the alternating current cycle output of the reed sufficiently to keep the reed output in step with the ticks of the Watch.

The reed output is alternating current at 15 cycles per second. This is subjected to full Wave rectification so as to produce direct current at 30 pulses per second. The pulses of this 30 pulse direct current are peaked for maximum eciency and then are impressed upon field poles of the watch tick governed motor. There are four poles, one at each of the points of the compass and the diametrically opposite poles are alike in their polarity. The rotor operating between these poles also has four poles of which the diametrically opposite are alike.

The watch motor l', is accordingly a non self starting synchronous motor which will run at nhalf-rectied-A. C. Iniplaceof the Wave form of half wave A. C. the motor'hasbeen found to operate efficiently on Sil-cycle D` C. pulses.

The requirements f 'the device of this invention are such that the-fniotor will run under tlies conditions Vsince the l'limits to which the freed maybe varied from its natural vibration `are l'essthanthe limits within which the motor will `run.

Itis -to 'be understood that v'many variations in 'the actual values given, such/afs` frequencies and 'time periods, may be used Without departing fromthe spirit of the invention.

What'Ic'laimim Y i E1.-.I`n 'a device of the character described, a

diiierentialdevice adapted to' be operated-'jointly by a current of a given frequency and one of regulated frequency, an indicator adapted to register the result of the operation of said differential device, automatic delay means adapted to maintain said indicator in inoperative relation with said dinerential device for a controlled period of time, automatically operated means adapted to link and maintain said indicator in operative relation with said diierential device for a controlled period of time, means for positively holding said indicator in its iinal position and means for releasing said hoiding means.

2. In a. timing apparatus, a rotatable member, means for rotating said member at a speed dependent on the error in the rate of a device being timed, an indicator, means for coupling said indicator to said member, means for automatically uncoupling said indicator at the end oi a predetermined time interval, and means operated automatically preliminary to a second coupling operation for restoring said indicator.

3. In a timing apparatus, an indicator, a member which is rotated at a speed dependent on the `error in the rate of a device being timed, means including a clutch magnet for coupling said indicator to said member, a restoring magnet, means including a switch for energizing said restoring magnet, a timing device started by the operation Aof said switch, and means including said device for automatically deenergizing said restoring magnet, for energizing said clutch magnet, and for deenergizing said clutch magnet after a predetermined time.

4. A watch timing apparatus operating through a predetermined cycle having means for converting the sounds of a timepiece into alternating current having a phase comparable with the timepiece sounds, a source of alternating current of a given frequency, means for producing a second alternating current, a differential device operable jointly by said nrst alternating current and said second alternating current, a differential indicator adapted to register the result of the operation of said differential device, means adapted to link said diierential device and said differential indicator for a controlled period of time, a cycle indicator adapted to indicate the start and iinish of said controlled period of time, locking means adapted to hold said differential indicator in its registering position, means for returning said differential indicator to eiective zero position and Warning means operable upon the variation of the second alternating current beyond given limits.

WILLIAM OGLE BENNETT, JR.

REFERENCES CITED The following references are of record in the le of this patent:

` UNITED STATES PATENTS Number Number Number 2 382,470

Name Date Davis July 8, 1930 Turner Mar. 3, 1931 Legg Mar. 21, 1933 Young July 17, 1934 Poole Mar. 31, 1936 Toison Apr. 7, 1936 Norrman Oct. 27,1936 BlauY Apr. 20, 1937 Serriere Dec. 20, 1938 Blau et al. Feb. 28, 1939 Ruspoli Apr. 18, 1939 Fetter et al. Apr. 25, 1939 Norman et al Jan. 23, 1940 Hicks May 14, 1940 Femnausen May 13, 1941 FOREIGN PATENTS Country Date Germany Oct. 3, 1923 

